Texas Instruments AMC3336 Precision Isolated Delta-Sigma Modulator

Texas Instruments AMC3336 Precision Isolated Delta-Sigma (ΔΣ) Modulator is optimized for high-impedance AC voltage measurements. The fully integrated, isolated DC/DC converter allows single-supply operation from the low-side of the device, which makes the device a unique solution for space-constrained applications. The reinforced capacitive isolation barrier is certified according to VDE V 0884-11 and UL1577 and supports a working voltage of up to 1.2kVRMS. The isolation barrier separates parts of the system that operate on different common-mode voltage levels and protects the low-voltage side from hazardous voltages and damage.

The input of the Texas Instruments AMC3336 is optimized for direct connection to a resistor network or other high-impedance voltage-signal source. The excellent DC accuracy and low temperature drift support accurate voltage measurements over the extended industrial temperature range from –40°C to +125°C. By using a digital filter (such as a sinc3 filter) to decimate the bitstream, the device can achieve 16 bits of resolution with a dynamic range of 85dB at a data rate of 78kSPS.

Features

  • 3.3V or 5V single supply with integrated DC/DC converter
  • ±1V input voltage range optimized for voltage measurements
  • 1GΩ (typ.) input resistance
  • Low DC errors
    • ±0.3mV (max.) offset error
    • ±4µV/°C (max.) offset drift
    • ±0.2% (max.) gain error
    • ±40ppm/°C (max) gain drift
  • 90kV/µs (min.) high CMTI
  • System-level diagnostic features
  • Low EMI (meets CISPR-11 and CISPR-25 standards)
  • Safety-related certifications
    • 6000VPEAK reinforced isolation per DIN VDE V 0884-11
    • 4250VRMS isolation for 1 minute per UL1577
  • Fully specified over the extended industrial temperature range (–40°C to +125°C)

Applications

  • Isolated voltage sensing in
    • Motor drives
    • Photovoltaic inverters
    • Power delivery systems
    • Protection relays

Functional Block Diagram

Block Diagram - Texas Instruments AMC3336 Precision Isolated Delta-Sigma Modulator
Publicado: 2021-05-26 | Actualizado: 2022-03-11